ED is a common occurrence after SCI, occurring in up to 80% of men, and results from disruption of the nerve pathways essential for erection (24,25). Different degrees of ED may occur depending on the spinal cord level of injury (LOI), extent of lesion and timing from injury. Reflexogenic erections can occur with lesions above L3 or L4 when the erectile spinal reflex arc remains intact. Psychogenic erections can occur with low lesions in the sacral and lumbar spinal cord but may not occur in complete lesions above T9 that can damage sympathetic outflow. Additionally, reflexogenic erections are not likely to occur in the spinal shock period that occurs after the initial cord trauma. Conversely, their occurrence may signal that the period of shock is over (26). Typically SCI affects younger men in their “sexual prime” and ED is associated with decreased quality of life (27).

No nitrate-based drugs should be given to men with suspected heart attacks if they have taken PDE5i medications within 24 hours. Combining PDE5i with nitrate-based medications can cause a severe and dramatic drop in blood pressure with potentially very dangerous consequences. This is also why someone should absolutely never share PDE5i medications with anyone else. If they happen to be taking one of the drugs that interacts dangerously with PDE5i medications, the results could be very serious. If there is any question about possible drug interactions, always check with a doctor or pharmacist.


Erosion of the prosthesis, whereby it presses through the corporal tissue into the urethra, may occur. Symptoms and signs may include pain, blood in the urine, discharge, abnormal urine stream, and malfunction. If the prosthesis erodes into the urethra, a physician must remove it. If the other cylinder remains intact, it can be left in place. A physician leaves a catheter in place to allow the urethra to heal.


Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain a hard enough erection for satisfactory completion of sexual activity. Erectile dysfunction is different from other health conditions that interfere with male sexual function, such as lack of sexual desire (decreased libido) and problems with ejaculation release of the fluid from the penis (ejaculatory dysfunction) and orgasm/climax (orgasmic dysfunction), and penile curvature (Peyronie's disease), although these problems may also be present. ED affects about 50% of men age 40 and over. This article focuses on the evaluation and treatment of erectile dysfunction.
No nitrate-based drugs should be given to men with suspected heart attacks if they have taken PDE5i medications within 24 hours. Combining PDE5i with nitrate-based medications can cause a severe and dramatic drop in blood pressure with potentially very dangerous consequences. This is also why someone should absolutely never share PDE5i medications with anyone else. If they happen to be taking one of the drugs that interacts dangerously with PDE5i medications, the results could be very serious. If there is any question about possible drug interactions, always check with a doctor or pharmacist.
If you can't take one of these oral medications, your physician may have you try Caverject (alprostadil for injection), a hormone that you inject into your penis using a fine needle, or Muse (alprostadil urogenital), a tiny suppository that you insert into the tip of the penis. Both of these will bring on an erection within five to 15 minutes without sexual stimulation.
Quitting smoking, exercising regularly, losing excess weight, curtailing excessive alcohol consumption, controlling hypertension, and optimizing blood glucose levels in patients with diabetes are not only important for maintaining good health but also may improve or even prevent progression of erectile dysfunction. It is unclear if such lifestyle changes can reverse erectile dysfunction. However, lifestyle improvements may prevent progression of the erectile dysfunction. Some studies suggest that men who have made lifestyle improvements experience increased rates of success with oral medications.
Experiencing ED can also be a reason to try not penetrative sex.  Try planning a sex session with your partner hat isn't focused on your erection at all.  Things like kissing, licking, sucking, foreplay and teasing all are super stimulating and don't focus on penetration.  Feel free to bring each other to orgasm using these ideas and see if you are able to relax and enjoy the experience.  Many men feel like failures when their erections become unreliable.  Having a few successful sexual sessions that lead to orgasm without penetration can put the fun back into having sex.  Many couples find success using this technique and begin to reengage sexually instead of avoiding being sexual for fear of failure.

Watts and coworkers, in their review article, make several points about this ED/CAD nexus. Endothelial dysfunction is present in both CVD and ED, and is linked through the NO mechanism. The authors note that PDE5 inhibitors improve endothelial function and have a salutary effect on both CVD and ED. Both ED and cardiac disease respond to modifications in lifestyle as well as pharmacologic manipulation. These authors also report that the presence of ED gives the clinician an opportunity to assess CVD and prevention as well.20


Induction of erection occurs after stimulation of the cavernous and pelvic nerve plexus. Conversely, stimulation of the sympathetic trunk leads to detumescence. The reflex erectile response requires that the sacral reflex arc remain intact. Tactile and sensory signals are received by the somatic sensory pathways and integrate with parasympathetic nuclei within the sacral spinal cord (S2-4) leading to induction of erection via cholinergic signaling. These reflexogenic erections remain intact with upper motor neuron injuries. Psychogenic erections do not require that the sacral reflex arc remain intact. In a cat models, spinal cord removal below L4/L5 led to absence of a reflexogenic erection but stimulation of the medial preoptic area (MPOA) or placement near a female cat in heat led to erection (5,6). Psychogenic erections occur via induction of central pathways traveling from the brain through the sympathetic chain. Non-penile sensory pathways induced by sight, sound, touch and smell travel through the MPOA to the erection centers within the cord T11-L2, and S2-S4 to induce erections (7). When a sacral lower motor neuron injury is present in men, below T12 these types of erections are more likely to occur (8). Spinal cord lesions above T9 are not associated with psychogenic erections (9). Rigidity of erections is less with psychogenic erections because the thoracolumbar sympathetic outflow may contain a decreased concentration of neurons compared to the parasympathetic outflow from the sacral spinal cord.
In most healthy men, some of the drug will remain in the body for more than two days after a single dose of tadalafil. Metabolism (clearing of the drug from the body) of tadalafil can be slowed by liver disease, kidney disease, and concurrent use of certain medications (such as erythromycin, ketoconazole, and protease inhibitors). Slowed breakdown allows tadalafil to stay in the body longer and potentially increase the risk for side effects. Therefore, doctors have to lower the dose and frequency of tadalafil in the following examples:
The first stem cell study for the treatment of ED was published in 2004. This study used embryonic stem cells to treat ED. At this time, there is a total of 36 published basic studies assessing stem cell therapy for ED, with two clinical trials. The mechanism of action of stem cells is to generate angiogenesis with subsequent increase in cavernosal smooth muscle cells within the corporal bodies.46
Also called vacuum devices, penile pumps are devices that are placed over the penis to draw blood into the shaft. Once the vacuum creates an erection, the retaining band is slid down to the lower end of the penis and the pump is removed. An erection typically will last long enough for intercourse but your penis may be cold to the touch and the rubber band may restrict ejaculation.22
Alprostadil should not be used in men with urethral stricture (scarring and narrowing of the tube that urine and the ejaculate pass through), balanitis (inflammation/infection of the glans [tip] of the penis, severe hypospadias (a condition where the opening of the urethra is not at the tip of the penis, rather on the underside of the penis), penile curvature (abnormal bend to the penis), and urethritis (inflammation/infection of the urethra).

The role of the endothelium in ED has been noted for a number of years and the overlapping of ED and other conditions, especially coronary heart disease, CVD, affecting endothelial function/dysfunction, is clearly present. The endothelial cell is now known to affect vascular tone and impact the process of atherosclerosis, and impacting ED, CVD and peripheral vascular disease.16
The inflatable type of device consists of cylinders that are implanted in the corpora cavernosa, a fluid reservoir implanted in the abdomen, and a pump placed in the scrotum. The man squeezes the pump to move fluid into the cylinders and cause them to become rigid. (He reverses the process by squeezing the pump again.) While these devices allow for intermittent erections, they have a slightly higher malfunction rate than the silicon rods.
Modern drug therapy for ED made a significant advance in 1983, when British physiologist Giles Brindley dropped his trousers and demonstrated to a shocked Urodynamics Society audience his papaverine-induced erection.[35] The drug Brindley injected into his penis was a non-specific vasodilator, an alpha-blocking agent, and the mechanism of action was clearly corporal smooth muscle relaxation. The effect that Brindley discovered established the fundamentals for the later development of specific, safe, and orally effective drug therapies.[36][better source needed][37][better source needed]
PDE5i for ED in patients with MS can be considered as reasonably effective and safe. Fowler et al. performed a randomized, multicenter, double-blind, flexible dose trial with open label extensions comparing sildenafil to placebo (75). A nearly 4-fold increase in effective erections was noted in the treatment arm, 96% vs. 24%. Sexual satisfaction and overall satisfaction were also improved in the treatment group based on IIEF scores, and quality of life assessments. Lombardi et al. evaluated tadalafil use in men with MS (71). Seventy eight percent of the men responded with improved erections, better quality of life with regards to sexual function, partner relationship and family life. Just less than half the men who responded to the tadalafil did so at the lower dosage of 10 mg. Subjects in either studies did not have any significant adverse side effects beyond flushing, and headache with PDE5i use.

PDE5 inhibitors, the primary second-line therapy, have been the mainstay of ED treatment since the release of sildenafil (Viagra) in 1998, with the subsequent development of many others, and still more in the development stage. These medications do improve erectile quality for the majority of men, and they work by enhancing blood flow in the corpora cavernosa. These medications are generally used on demand and need to be taken about an hour before sexual intimacy. Tadalafil (Cialis) is longer acting and does come in a daily preparation potentially eliminating the ‘on-demand’ need. The daily dosing of tadalafil, 2.5–5 mg\day, has also been approved by the FDA for treatment of symptoms of BPH.41 PDE5 inhibitors are contraindicated in men taking nitrates, but otherwise PDE5 inhibitors are very safe and effective. When PDE5 inhibitors are coadministered with nitrates, pronounced systemic vasodilation and severe hypotension are possible. Many patients with ED are elderly and have the same risk factors as patients with CAD, so these drug combinations are commonly considered or encountered in clinical practice.42
Talk with your doctor about going to a counselor if psychological or emotional issues are affecting your ED. A counselor can teach you how to lower your anxiety or stress related to sex. Your counselor may suggest that you bring your partner to counseling sessions to learn how to support you. As you work on relieving your anxiety or stress, a doctor can focus on treating the physical causes of ED.
Under normal circumstances, when a man is sexually stimulated, his brain sends a message down the spinal cord and into the nerves of the penis. The nerve endings in the penis release chemical messengers, called neurotransmitters, that signal the corpora cavernosa (the two spongy rods of tissue that span the length of the penis) to relax and fill with blood. As they expand, the corpora cavernosa close off other veins that would normally drain blood from the penis. As the penis becomes engorged with blood, it enlarges and stiffens, causing an erection. Problems with blood vessels, nerves, or tissues of the penis can interfere with an erection.
Herbal supplements such as ginkgo biloba, saw palmetto, and yohimbe have been touted as sexual enhancers, and some men have been tempted to try them to treat erectile dysfunction. Bennett warns, however, that none has been approved by the FDA or even shown by any reliable studies to prevent, treat, or improve erectile dysfunction. Moreover, supplements are unregulated and can have many side effects or interfere with prescribed medications you’re already taking. Don’t jeopardize your health by taking a supplement to treat erectile dysfunction without first talking with your doctor.

Impotence, also called erectile dysfunction, in general, the inability of a man to achieve or maintain penile erection and hence the inability to participate fully in sexual intercourse. In its broadest sense the term impotence refers to the inability to become sexually aroused; in this sense it can apply to women as well as to men. In common practice, however, the term has traditionally been used to describe only male sexual dysfunctions. Professional sex therapists, while they identify two distinct dysfunctions as forms of impotence, prefer not to use the term impotence per se. Thus, because of its pejorative connotation in lay usage and because of confusion about its definition, the word impotence has been eliminated from the technical vocabulary in favour of the term “erectile dysfunction.”


Alprostadil may also be administered into the urethral opening of the penis. In MUSE (medical urethral system for erection), the man inserts a thin tube the width of a vermicelli noodle into his urethral opening and presses down on a plunger to deliver a tiny pellet containing alprostadil into his penis. The drug takes about 10 minutes to work and the erection lasts about an hour. The main side effect is a sensation of pain and burning in the urethra, which can last about five to 15 minutes.
Having erection trouble from time to time isn't necessarily a cause for concern. If erectile dysfunction is an ongoing issue, however, it can cause stress, affect your self-confidence and contribute to relationship problems. Problems getting or keeping an erection can also be a sign of an underlying health condition that needs treatment and a risk factor for heart disease.
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